It is known, from DK-PS No. 156,808, to cut free the rectum, the so-called fatty end, of a carcass of a slaughtered animal by means of a rotating tubular drill or a rotating tubular knife, where the knife is placed opposite the rectum of the carcass in such a manner that the axis of rotation of the knife is placed in extension of the center line of the rectum and the spine of the carcass. Subsequently, the rotating drilling pipe is moved forward. The movement by the drill is guided by a pin placed in the tubular drill and inserted in the anus. According to DK-PS No. 156,808, the drill is removed after the cutting procedure.
Attempts at pulling out the rectum in extension of the center line thereof are also known, for example, DK-PS No. 129,495, in the rectum is retained outside the animal on the back of the carcass while the remaining intestinal portions are cut free. A condition for pulling out the rectum in extension of its center line is that the rectum is so resilient that it can be kept intact outside the carcass. It turned out, however, that the resilience of the rectum varies much from animal to animal, especially in connection with pigs. As a result, the rupture of the rectum often arises, particularly with sows.
Both when the rectum is left inside the carcass after the cutting procedure and when attempts are made at pulling out the rectum whereby the rectum ruptures, a risk exists of the visceral contents sieving out into the meat and thereby contaminating the meat. Contamination caused by sieving visceral contents in the latter process turned out to present severe problems of bacteria, such as Salmonella and Yersenia, in connection with meat from the bacon factories. Accordingly, the importance of avoiding in any possible way a sieving of visceral contents is recognized. The rectum cut free cannot therefore be left free in the carcass after the cutting free procedure. Nor should rupture of the rectum be allowed during attempts to pull it backwards relative to the hind part of the carcass and retain it in the drill until the remaining portion of the intestinal portions have been cut free. Although the remaining intestinal portions are cut free without causing any sieving of the visceral contents, a risk exists that some of the visceral contents nevertheless escape in connection with releasing the rectum from the drill.